dbms_job not running

I have create a job using dbms_job.isubmit but the job just will not execute when scheduled. I am new to Oracle Job package and I cannot figure out why my scheduled job will not run when scheduled.

If I run the job with dbms_job.run(1000) the job executes the procedure just fine.

Any suggestions as to what I am doing wrong? Thanks in advance...

' created job to call package procedure using: Want to run every two minutes, every day of the week.

begin
 dbms_job.isubmit(1000, 'mypackage.mysub;', SYSDATE,'SYSDATE + 2/1440');
end;

Query job and it Looks like everything is fine:

  SELECT job, next_date, next_sec, failures, broken, SUBSTR(what,1,40) DESCRIPTION,sysdate
  FROM user_jobs

1000,9/6/2005 4:42:31 PM,16:42:31,0,N,mypackage.mysub;,9/6/2005 4:47:13 PM Received on Tue Sep 06 2005 - 15:50:34 CDT